PTGS2 and tongue squamous cell carcinoma: Resection samples from 90 eligible mobile tongue SCC patients (47 males, 43 females) were analysed using a set of possible new and previously proposed immunohistochemical prognostic markers including microvessel density (CD31 and factor VIII), cyclooxygenase-2 (COX-2), the laminin-5 γ2-chain, integrin αvβ6 and matrix metalloproteinases (MMP-2, -7, -8, -9, -20, and -28).